This proposal has three broad long-term objectives: 1) to determine relatedness, based on selected phenotypes, of world-wide geographic populations of Aedes albopictus (Skuse) (Diptera: Culicidae), 2) to provide a research base for extended studies after the completion of the present research, and 3) to provide research experiences for undergraduate students interested in health professions. Aedes albopictus, an efficient vector of several viral diseases, has recently been introduced into North America. The immediate-research objectives of this proposal are to: 1) chemically characterize by capillary gas chromatography electron impact mass spectrometry the major (compounds greater than 0.5% relative abundance) cuticular hydrocarbon components of adult male and female Ae. albopictus, and 2) quantitatively characterize, using capillary gas chromatography, the cuticular hydrocarbon profiles of Ae. albopictus in terms of individual and geographic variation. Cuticular hydrocarbons will be extracted from single specimens. Cuticular hydrocarbon peaks, utilizing capillary gas chromatography analysis, obtained from specimens of at least 14 populations from Asia and North America will be utilized as character sets for multivariate statistical analysis of geographic variation.